diff options
| -rw-r--r-- | stats/CMakeLists.txt | 2 | ||||
| -rw-r--r-- | stats/statsaxis.cpp | 394 | ||||
| -rw-r--r-- | stats/statsaxis.h | 85 |
3 files changed, 481 insertions, 0 deletions
diff --git a/stats/CMakeLists.txt b/stats/CMakeLists.txt index a03ff0c1a..c8ab86997 100644 --- a/stats/CMakeLists.txt +++ b/stats/CMakeLists.txt @@ -7,6 +7,8 @@ include_directories(. set(SUBSURFACE_STATS_SRCS legend.h legend.cpp + statsaxis.h + statsaxis.cpp statscolors.h statscolors.cpp statsvariables.h diff --git a/stats/statsaxis.cpp b/stats/statsaxis.cpp new file mode 100644 index 000000000..46351a534 --- /dev/null +++ b/stats/statsaxis.cpp @@ -0,0 +1,394 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "statsaxis.h" +#include "statstranslations.h" +#include "statsvariables.h" +#include "core/pref.h" +#include "core/subsurface-time.h" +#include <math.h> // for lrint +#include <numeric> +#include <QChart> +#include <QFontMetrics> +#include <QLocale> + +StatsAxis::StatsAxis(bool horizontal) : horizontal(horizontal) +{ +} + +StatsAxis::~StatsAxis() +{ +} + +std::pair<double, double> StatsAxis::minMax() const +{ + return { 0.0, 1.0 }; +} + +// Guess the number of tick marks based on example strings. +// We will use minimum and maximum values, which are not necessarily the +// maximum-size strings especially, when using proportional fonts or for +// categorical data. Therefore, try to err on the safe side by adding enough +// margins. +int StatsAxis::guessNumTicks(const QtCharts::QChart *chart, const QtCharts::QAbstractAxis *axis, const std::vector<QString> &strings) const +{ + QFont font = axis->labelsFont(); + QFontMetrics fm(font); + int minSize = fm.height(); + for (const QString &s: strings) { + QSize size = fm.size(Qt::TextSingleLine, s); + int needed = horizontal ? size.width() : size.height(); + if (needed > minSize) + minSize = needed; + } + + // Add space between labels + if (horizontal) + minSize = minSize * 3 / 2; + else + minSize *= 2; + QRectF chartSize = chart->plotArea(); + double availableSpace = horizontal ? chartSize.width() : chartSize.height(); + int numTicks = lrint(availableSpace / minSize); + return std::max(numTicks, 2); +} + +ValueAxis::ValueAxis(double min, double max, int decimals, bool horizontal) : StatsAxisTemplate(horizontal), + min(min), max(max), decimals(decimals) +{ +} + +std::pair<double, double> ValueAxis::minMax() const +{ + return { QValueAxis::min(), QValueAxis::max() }; +} + +static QString makeFormatString(int decimals) +{ + return QStringLiteral("%.%1f").arg(decimals < 0 ? 0 : decimals); +} + +void ValueAxis::updateLabels(const QtCharts::QChart *chart) +{ + using QtCharts::QValueAxis; + + // Avoid degenerate cases + if (max - min < 0.0001) { + max += 0.5; + min -= 0.5; + } + + QLocale loc; + QString minString = loc.toString(min, 'f', decimals); + QString maxString = loc.toString(max, 'f', decimals); + int numTicks = guessNumTicks(chart, this, { minString, maxString}); + + // Use full decimal increments + double height = max - min; + double inc = height / numTicks; + double digits = floor(log10(inc)); + int digits_int = lrint(digits); + double digits_factor = pow(10.0, digits); + int inc_int = std::max((int)ceil(inc / digits_factor), 1); + // Do "nice" increments of the leading digit: 1, 2, 4, 5. + if (inc_int > 5) + inc_int = 10; + if (inc_int == 3) + inc_int = 4; + inc = inc_int * digits_factor; + if (-digits_int > decimals) + decimals = -digits_int; + + setLabelFormat(makeFormatString(decimals)); + double actMin = floor(min / inc) * inc; + double actMax = ceil(max / inc) * inc; + int num = lrint((actMax - actMin) / inc); + setRange(actMin, actMax); + setTickCount(num + 1); +} + +CountAxis::CountAxis(int count, bool horizontal) : ValueAxis(0.0, (double)count, 0, horizontal), + count(count) +{ +} + +void CountAxis::updateLabels(const QtCharts::QChart *chart) +{ + QLocale loc; + QString countString = loc.toString(count); + int numTicks = guessNumTicks(chart, this, { countString }); + + // Get estimate of step size + if (count <= 0) + count = 1; + // When determining the step size, make sure to round up + int step = (count + numTicks - 1) / numTicks; + if (step <= 0) + step = 1; + + // Get the significant first or first two digits + int scale = 1; + int significant = step; + while (significant > 25) { + significant /= 10; + scale *= 10; + } + + for (int increment: { 1, 2, 4, 5, 10, 15, 20, 25 }) { + if (increment >= significant) { + significant = increment; + break; + } + } + step = significant * scale; + + // Make maximum an integer number of steps, equal or greater than the needed counts + int num = (count - 1) / step + 1; + int max = num * step; + numTicks = num + 1; // There is one more tick than steps + + setLabelFormat("%.0f"); + setRange(0, max); + setTickCount(numTicks); +} + +CategoryAxis::CategoryAxis(const std::vector<QString> &labels, bool horizontal) : StatsAxisTemplate(horizontal) +{ + for (const QString &s: labels) + append(s); +} + +void CategoryAxis::updateLabels(const QtCharts::QChart *) +{ +} + +// A small helper class that makes strings unique. We need this, +// because QCategoryAxis can only handle unique category names. +// Disambiguate strings by adding unicode zero-width spaces. +// Keep track of a list of strings and how many spaces have to +// be added. +class LabelDisambiguator { + using Pair = std::pair<QString, int>; + std::vector<Pair> entries; +public: + QString transmogrify(const QString &s); +}; + +QString LabelDisambiguator::transmogrify(const QString &s) +{ + auto it = std::find_if(entries.begin(), entries.end(), + [&s](const Pair &p) { return p.first == s; }); + if (it == entries.end()) { + entries.emplace_back(s, 0); + return s; + } else { + ++(it->second); + return s + QString(it->second, QChar(0x200b)); + } +} + +HistogramAxis::HistogramAxis(std::vector<HistogramAxisEntry> bins, bool horizontal) : StatsAxisTemplate(horizontal), + bin_values(std::move(bins)) +{ + if (bin_values.size() < 2) // Less than two makes no sense -> there must be at least one category + return; + + LabelDisambiguator labeler; + for (HistogramAxisEntry &entry: bin_values) + entry.name = labeler.transmogrify(entry.name); + + // The caller can declare some bin labels as preferred, when there are + // too many labels to show all. Try to infer the preferred step size + // by finding two consecutive preferred labels. This supposes that + // the preferred labels are equi-distant and that the caller does not + // use large prime (or nearly prime) steps. + auto it1 = std::find_if(bin_values.begin(), bin_values.end(), + [](const HistogramAxisEntry &e) { return e.recommended; }); + auto next_it = it1 == bin_values.end() ? it1 : std::next(it1); + auto it2 = std::find_if(next_it, bin_values.end(), + [](const HistogramAxisEntry &e) { return e.recommended; }); + preferred_step = it2 == bin_values.end() ? 1 : it2 - it1; + setMin(bin_values.front().value); + setMax(bin_values.back().value); + setStartValue(bin_values.front().value); + setLabelsPosition(QCategoryAxis::AxisLabelsPositionOnValue); +} + +std::pair<double, double> HistogramAxis::minMax() const +{ + if (bin_values.size() < 2) // Less than two makes no sense -> there must be at least one category + return { 0.0, 1.0 }; + return { QValueAxis::min(), QValueAxis::max() }; +} + +// Initialize a histogram axis with the given labels. Labels are specified as (name, value, recommended) triplets. +// If labels are skipped, try to skip it in such a way that a recommended label is shown. +// The one example where this is relevant is the quarterly bins, which are formated as (2019, q1, q2, q3, 2020, ...). +// There, we obviously want to show the years and not the quarters. +void HistogramAxis::updateLabels(const QtCharts::QChart *chart) +{ + if (bin_values.size() < 2) // Less than two makes no sense -> there must be at least one category + return; + + // There is no clear all labels function in QCategoryAxis!? You must be kidding. + for (const QString &label: categoriesLabels()) + remove(label); + if (count() > 0) + qWarning("HistogramAxis::updateLabels(): labels left after clearing!?"); + + std::vector<QString> strings; + strings.reserve(bin_values.size()); + for (auto &[name, value, recommended]: bin_values) + strings.push_back(name); + int maxLabels = guessNumTicks(chart, this, strings); + + int step = ((int)bin_values.size() - 1) / maxLabels + 1; + if (step < preferred_step) { + if (step * 2 > preferred_step) { + step = preferred_step; + } else { + int gcd = std::gcd(step, preferred_step); + while (preferred_step % step != 0) + step += gcd; + } + } else if (step > preferred_step) { + int remainder = (step + preferred_step) % preferred_step; + if (remainder != 0) + step = step + preferred_step - remainder; + } + int first = 0; + if (step > 1) { + for (int i = 0; i < (int)bin_values.size(); ++i) { + const auto &[name, value, recommended] = bin_values[i]; + if (recommended) { + first = i % step; + break; + } + } + } + for (int i = first; i < (int)bin_values.size(); i += step) { + const auto &[name, value, recommended] = bin_values[i]; + append(name, value); + } +} + +// Helper function to turn days since "Unix epoch" into a timestamp_t +static const double seconds_in_day = 86400.0; +static timestamp_t double_to_timestamp(double d) +{ + return timestamp_t{ lrint(d * seconds_in_day) }; +} + +// Turn double to (year, month) pair +static std::pair<int, int> double_to_month(double d) +{ + struct tm tm; + utc_mkdate(double_to_timestamp(d), &tm); + return { tm.tm_year, tm.tm_mon }; +} + +// Increase (year, month) pair by one month +static void inc(std::pair<int, int> &ym) +{ + if (++ym.second >= 12) { + ++ym.first; + ym.second = 0; + } +} + +static std::array<int, 3> double_to_day(double d) +{ + struct tm tm; + utc_mkdate(double_to_timestamp(d), &tm); + return { tm.tm_year, tm.tm_mon, tm.tm_mday }; +} + +// This is trashy: to increase a day, turn into timestamp and back. +// This surely can be done better. +static void inc(std::array<int, 3> &ymd) +{ + struct tm tm = { 0 }; + tm.tm_year = ymd[0]; + tm.tm_mon = ymd[1]; + tm.tm_mday = ymd[2] + 1; + timestamp_t t = utc_mktime(&tm); + utc_mkdate(t, &tm); + ymd = { tm.tm_year, tm.tm_mon, tm.tm_mday }; +} + +// Use heuristics to determine the preferred day/month format: +// Try to see whether day or month comes first and try to extract +// the separator character. Returns a (day_first, separator) pair. +static std::pair<bool, char> day_format() +{ + const char *fmt = prefs.date_format; + const char *d, *m, *sep; + for (d = fmt; *d && *d != 'd' && *d != 'D'; ++d) + ; + for (m = fmt; *m && *m != 'm' && *m != 'M'; ++m) + ; + for(sep = std::min(m, d); *sep == 'm' || *sep == 'M' || *sep == 'd' || *sep == 'D'; ++sep) + ; + return { d < m, *sep ? *sep : '.' }; +} + +// For now, misuse the histogram axis for creating a time axis. Depending on the range, +// create year, month or day-based bins. This is certainly not efficient and may need +// some tuning. However, it should ensure that no crazy number of bins is generated. +// Ultimately, this should be replaced by a better and dynamic scheme +// From and to are given in seconds since "epoch". +static std::vector<HistogramAxisEntry> timeRangeToBins(double from, double to) +{ + // from and two are given in days since the "Unix epoch". + // The lowest precision we do is two days. + if (to - from < 2.0) { + double center = (from + to) / 2.0; + from = center + 1.0; + to = center - 1.0; + } + + std::vector<HistogramAxisEntry> res; + if (to - from > 2.0 * 356.0) { + // For two years or more, do year based bins + int year_from = utc_year(double_to_timestamp(from)); + int year_to = utc_year(double_to_timestamp(to)) + 1; + for (int year = year_from; year <= year_to; ++year) + res.push_back({ QString::number(year), date_to_double(year, 0, 0), true }); + } else if (to - from > 2.0 * 30.0) { + // For two months or more, do month based bins + auto year_month_from = double_to_month(from); + auto year_month_to = double_to_month(to); + inc(year_month_to); + for (auto act = year_month_from; act <= year_month_to; inc(act)) { + double val = date_to_double(act.first, act.second, 0); + if (act.second == 0) + res.push_back({ QString::number(act.first), val, true }); + else + res.push_back({ monthname(act.second), val, false }); + } + } else { + // For less than two months, do date based bins + auto day_from = double_to_day(from); + auto day_to = double_to_day(to); + inc(day_to); + auto [day_before_month, separator] = day_format(); + QString format = day_before_month ? QStringLiteral("%1%2%3") + : QStringLiteral("%3%2%1"); + QString sep = QString(separator); + for (auto act = day_from; act < day_to; inc(act)) { + double val = date_to_double(act[0], act[1], act[2]); + if (act[1] == 0) { + res.push_back({ QString::number(act[0]), val, true }); + } else if (act[2] == 0) { + res.push_back({ monthname(act[1]), val, true }); + } else { + QString s = format.arg(QString::number(act[2]), sep, QString::number(act[1])); + res.push_back({s, val, true }); + } + } + } + return res; +} + +DateAxis::DateAxis(double from, double to, bool horizontal) : + HistogramAxis(timeRangeToBins(from, to), horizontal) +{ +} diff --git a/stats/statsaxis.h b/stats/statsaxis.h new file mode 100644 index 000000000..5c77189cc --- /dev/null +++ b/stats/statsaxis.h @@ -0,0 +1,85 @@ +// SPDX-License-Identifier: GPL-2.0 +// Supported chart axes +#ifndef STATS_AXIS_H +#define STATS_AXIS_H + +#include <vector> +#include <QBarCategoryAxis> +#include <QCategoryAxis> +#include <QValueAxis> + +namespace QtCharts { + class QChart; +} + +class StatsAxis { +public: + virtual ~StatsAxis(); + virtual void updateLabels(const QtCharts::QChart *chart) = 0; + virtual QtCharts::QAbstractAxis *qaxis() = 0; + // Returns minimum and maximum of shown range, not of data points. + virtual std::pair<double, double> minMax() const; +protected: + StatsAxis(bool horizontal); + int guessNumTicks(const QtCharts::QChart *chart, const QtCharts::QAbstractAxis *axis, const std::vector<QString> &strings) const; + bool horizontal; +}; + +// Small template that derives from a QChart-axis and defines +// the corresponding virtual axis() accessor. +template<typename QAxis> +class StatsAxisTemplate : public StatsAxis, public QAxis +{ + using StatsAxis::StatsAxis; + QtCharts::QAbstractAxis *qaxis() override final { + return this; + } +}; + +class ValueAxis : public StatsAxisTemplate<QtCharts::QValueAxis> { +public: + ValueAxis(double min, double max, int decimals, bool horizontal); +private: + double min, max; + int decimals; + void updateLabels(const QtCharts::QChart *chart) override; + std::pair<double, double> minMax() const override; +}; + +class CountAxis : public ValueAxis { +public: + CountAxis(int count, bool horizontal); +private: + int count; + void updateLabels(const QtCharts::QChart *chart) override; +}; + +class CategoryAxis : public StatsAxisTemplate<QtCharts::QBarCategoryAxis> { +public: + CategoryAxis(const std::vector<QString> &labels, bool horizontal); +private: + void updateLabels(const QtCharts::QChart *chart); +}; + +struct HistogramAxisEntry { + QString name; + double value; + bool recommended; +}; + +class HistogramAxis : public StatsAxisTemplate<QtCharts::QCategoryAxis> { +public: + HistogramAxis(std::vector<HistogramAxisEntry> bin_values, bool horizontal); +private: + void updateLabels(const QtCharts::QChart *chart) override; + std::pair<double, double> minMax() const override; + std::vector<HistogramAxisEntry> bin_values; + int preferred_step; +}; + +class DateAxis : public HistogramAxis { +public: + DateAxis(double from, double to, bool horizontal); +}; + +#endif |